“Some of the stuff up there, even the producers say they would not be able to spot it,” Downey told CBS 2’s Tony Aiello.

Kurniawan faces up to 20 years in prison when he’s sentenced in March. He also borrowed money against his collection of fake wines and owes a New York bank several million dollars.

Federal prosecutors said Kurniawan turned his California home into a wine factory. Restaurants sent him empty wine bottles, then he mixed together cheap wine and rebottled it as vintage wine.

“He made blends,” Downey said. “He was like a mad scientist.”

For example, Kurniawan phonied up two bottles of 1934 Romanee-Conti and sold them for $24,000. A fake double-magnum of 1947 Chateau Petrus was auctioned for $30,000.

But he made mistakes that raised eyebrows in the world of fine wine.

Kurniawan put up for auction bottles of Clos Saint-Denis from the 1940s and 1950s even though the winery didn’t start producing that appellation until the 1980s.

A New York auction house moved millions of dollars of wine provided by Kurniawan. Downey said collectors continued to buy even as suspicions about the vintner grew.

“A lot of these guys are stuck with millions of dollars in fake wine,” Downey said. “So they didn’t want to lose out on their investment, but it’s time to face the music. They can no longer have their head in the sand.